<!--
 * @Author: your name
 * @Date: 2021-03-21 18:40:46
 * @LastEditTime: 2021-03-31 15:45:54
 * @LastEditors: Please set LastEditors
 * @Description: In User Settings Edit
 * @FilePath: \undefinedd:\练习\蛇边界按钮.html
-->


<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    
    <style>
        *{
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        body{
            height: 100vh;
            display: flex;
            justify-content: center;
            align-items: center;
            background-color: rgb(4, 4, 19);
        }
        .night{
            position: relative;
            width: 300px;
            height: 100px;
            color: rgb(18, 190, 243);
            letter-spacing: 12px;
            font-size: 50px;
            line-height: 100px;
            text-align: center;
            /* background-color: rgb(31, 49, 133); */
            background-image: linear-gradient(90deg, rgb(40, 62, 161) 50%,rgb(31, 49, 133) 50% );
            text-transform: uppercase;
            user-select: none;
            text-decoration: none;
            overflow: hidden;
            box-shadow: inset 0 0 10px rgb(14, 20, 105),
            0 0 5px rgb(9, 208, 235);
            transition: all 0.5s;
            
        }
        .night:hover{
            text-shadow: 0 0 5px rgb(18, 190, 243),
            0 0 8px rgb(18, 190, 243),
            0 0 10px rgb(18, 190, 243); 
            background-image: linear-gradient(90deg, rgb(25, 38, 99) 50%,rgb(13, 22, 58) 50% );
            box-shadow: inset 0 0 10px rgb(14, 20, 105),
            0 0 5px rgb(9, 208, 235),
            0 0 10px rgb(9, 208, 235);
        }
            
        .night span{
            position: absolute;   
        }
        .night span:nth-child(1){
            top: 0;
            left: 0;
            width: 100%;
            height: 2px;
            background-image: linear-gradient(to right, transparent , rgb(0, 153, 255) );
            animation: move1 2s linear infinite;
        }
        @keyframes move1 {
            0%{
                transform: translateX(-100%);
            }
            100%{
                transform: translateX(100%);
            }
        }
        .night span:nth-child(2){
            top: 0;
            right: 0;
            width: 2px;
            height: 100%;
            transform: translateY(-100%);
            background-image: linear-gradient(to bottom,  transparent ,  rgb(0, 153, 255)  );            
            animation: move2 2s linear infinite;
            animation-delay: 1s;
        }
        @keyframes move2 {
           
            100%{
                transform: translateY(100%);
            }
        }
        .night span:nth-child(3){
            left: 0;
            bottom: 0;
            width: 100%;
            height: 2px;
            background-image: linear-gradient(to left, transparent , rgb(0, 153, 255) );
            animation: move3 2s linear infinite;
        }
        @keyframes move3 {
            0%{
                transform: translateX(100%);
            }
            100%{
                transform: translateX(-100%);
            }
        }
        .night span:nth-child(4){
            top: 0;
            left: 0;
            width: 2px;
            height: 100%;
            transform: translateY(100%);
            background-image: linear-gradient(to top, transparent , rgb(0, 153, 255) );
            animation: move4 2s linear infinite;
            animation-delay: 1s;
        }
        @keyframes move4 {
            100%{
                transform: translateY(-100%);
            }
        }
    </style>
</head>
<body>
    <a href="https://blog.csdn.net/luo1831251387?spm=1000.2115.3001.5343" class="night" target="blank">
        <span></span>
        <span></span>
        <span></span>
        <span></span>
          night
    </a>
</body>
</html>